Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)

тройная система

Topological Transformation of the Phase Diagram of the Ternary System Potassium Formate - Water - n.Butoxyethanol

Phase equilibria and critical phenomena in the ternary system potas­ sium formate - water - n.butoxyethanol, where a constituent binary liquid system is characterized by phase separation with a closed delamination region, were studied by means of the visual-polythermal method within 25-170°C. The temperature dependences of the com­ positions of the mixtures corresponding to the critical solubility points in the delamination region were determined.

Description of the chemical interaction in the system CaO-Al2O3-SiO2

In this study the construction of a phase tree and the description of the chemical interaction for the ternary oxide system CaO-Al2 O3 -SiO2 are given. Particular interest to a system consisting of oxides of calcium, aluminum and silicon is associated with the production of highly demanded functional materials with desired properties. Melts of the CaO-Al2 O3 -SiO2 system are of great theoretical and applied importance. This is due to the signifi cant role of melts of these oxides and their mixtures in metallurgy, ceramics production, and other industries.

Phase tree, forecast of crystallizing phases and description of chemical interaction in the system KCl–CaCl2–BaCl2

The construction of a phases tree of a ternary system with three binary compounds KCaCl3 , K2 BaCl4 , CaBaCl4 is given. The phase tree includes four secondary phase triangles CaCl2 –KCaCl3 –СаBaCl4 , CaBaCl4 –KCaCl3 –BaCl2 , KCaCl3 –BaCl2 –K2 BaCl4 and KCaCl3 –CaBaCl4 –KCl. These triangles are connected by three stable secants KCaCl3 –СаBaCl4 , KCaCl3 –BaCl2 , KCaCl3 –K2 BaCl4 . Crystallizing phases in stable and secant elements correspond to the simplex tops.


Методом сечений Мерцлина при 25.0 °С изучена диаграмма рас-
творимости тройной системы нитрат калия–вода–н-бутоксиэта-
нол. Установлено, что она относится к диаграммам тройных
систем с высаливанием. Экспериментально и графически
определен состав критической точки растворимости области
расслоения. На полях моновариантных состояний построены
13 нод, определены составы равновесных жидких фаз и рас-
считан коэффициент распределения н-бутоксиэтанола между


Проведен сравнительный анализ результатов политермического
исследования высаливающего действия нитратов щелочных ме-
таллов (Na, K, Cs) на двойную систему вода – триэтиламин, ха-
рактеризующуюся расслаиванием с нижней критической темпе-
ратурой растворения (НКТР). Обнаружено, что нитраты щелочных
металлов, подвергающиеся в водно-органических растворителях
гомоселективной сольватации, понижают НКТР этой двойной си-
стемы, т. е. обладают высаливающим действием.
Установлено, что уменьшение радиуса катиона соли в ряду

Phase Diagrams of the Ternary Systems Potassium Carbonate + Water + Hydrocarbon at 25°С

The phase diagrams of the ternary systems potassium carbo- nate+water+hydrocarbon (toluene, n.dodecane) at 25°С were first studied by means of the methods of sections and isothermal titration. The phase diagrams of both systems belong to those of ternary systems with salting-out of the binary heterogeneous system. Potassium carbon- ate sesquihydrate is the solid phase of monotectic equilibrium. Nine tie lines were drawn on the delamination field of the phase diagram of each ternary system.

Phase Equilibria in the Ternary System “Potassium Iodide – Water – Tert-Butyl Alcohol” within 5–30°C

Studying of the influence of the salt nature and temperature on the liquid-liquid equilibrium in the ternary systems “salt – binary solvent” is topical for the development of the salting-in–salting- out theory. In addition, the ternary potassium iodide-water-alcohol systems are constituents of the quaternary iodine – potassium iodide – water – alcohol ones, studying of which is of practical interest in terms of determining the mixed solvent compositions with the highest iodine-dissolving power.

Data Approximation for Plotting the Binodal Curve on the Phase Diagrams of Some Ternary Salt – Water – Isopropyl (n-Propyl) Alcohol Systems

A brief review of computational methods for the liquid-liquid equilibrium has been carried out, and their capabilities and limitations have been shown. Complications of such computational models for the liquid–liquid–solid equilibrium lead to a decreased accuracy of calculations. In this case, it is advisable for researchers to make use of the approximation of experimental data on the liquid – liquid and liquid – liquid – solid equilibria.

Extractive Crystallization of Salt and Phase Equilibria in the Ternary System Sodium Nitrate – Water – Dipropylamine

Phase equilibria in the ternary system sodium nitrate – water – dipropylamine where the constituent binary liquid system is characterized by a trend to form a lower critical solution temperature (LCST) were studied using the visual-polythermal method in the range ?10.0–90.0° C. It was found that the introduction of sodium nitrate into the water – dipropylamine system led to a significant decrease in the mutual solubility of the components.

Phase Equilibria and Salting Out of Butyric Acid in the Sodium Chloride – Water – Butyric Acid Ternary System

Phase equilibria in the water–butyric acid binary system in the range of ?10?0° C and in the sodium chloride–water–butyric acid ternary system in the range of 10.0?60.0° C were studied using the visual polythermal method. The phase diagram of the water–butyric acid binary system at ?9.5° C is characterized by eutectic equilibrium, the solid phases of which being ice and butyric acid crystals. The metastable delamination range was found on the ice crystallization field, bounded by a binodal curve with an upper critical solution temperature of ?3.7° C.